Disease relevance of pll

• Remarkably, unlike the DmMyD88/tube/pelle/cactus gene cassette of the Toll pathway, wek plays a minimal role, if any, in the immune defense against Gram-positive bacteria and fungi [1].

High impact information on pll

• DNA sequence analysis revealed that pelle encodes a protein of 501 amino acids, the last 292 of which comprise a protein kinase catalytic domain [2].
• The pelle gene is required for the nuclear import of dorsal protein that establishes dorsoventral polarity in Drosophila embryos [2].
• The Toll, tube, pelle, cactus, and dorsal genes also appear to be involved in Drosophila immune response [3].
• We further demonstrated that signal-dependent dorsal phosphorylation is modulated by three intracellular proteins, pelle, tube, and cactus [4].
• We demonstrate that fusion of the pelle catalytic domain to the transmembrane receptor torso is sufficient to induce ventral fates; this activity is independent of Toll or tube [5].

Biological context of pll

• We also characterize a large collection of pelle alleles, identifying the molecular lesions in these alleles and their effects on Pelle autophosphorylation, Tube phosphorylation and Tube relocalization [6].
• Here we demonstrate that tube mutations also have a zygotic effect on pupal morphology and that this phenotype is shared by mutations in Toll and pelle, two genes with apparent intracellular roles in determining dorsoventral polarity [7].
• We find that spätzle, tube, and pelle, but not easter, are necessary for muscle development [8].

Anatomical context of pll

• We propose a model wherein tube activates pelle by recruiting it to the plasma membrane, thereby propagating the axis-determining signal [5].
• The hemocyte density of mutant Toll, tube or pelle hemolymph is significantly lower than that of the wild type [9].
• Both tube and pelle are also important zygotically for survival: at least 30% of the zygotes lacking either tube or pelle die before adult stages, while 90-95% of tube- pelle- double mutant zygotes die [10].

Associations of pll with chemical compounds

• Genetic studies have identified three intracellular components whose activity is required for activation of dl: Toll, a transmembrane receptor; pelle (pll), a serine/threonine protein kinase; and tube, a protein of unknown function [11].
• Pellino is a Drosophila protein originally isolated in a two-hybrid screen for proteins interacting with the serine/threonine kinase, pelle [12].

Regulatory relationships of pll

• Based on these and other results, we propose a model in which pll receives a signal from activated Toll and phosphorylates tube, which then participates directly in dl activation [11].

Other interactions of pll

• tube and pelle are two of the maternally transcribed genes required for dorsal-ventral patterning of the Drosophila embryo [10].
• Lastly, we find that fusion of the tube protein to torso also induces ventral fates, but only in the presence of functional pelle [5].

Analytical, diagnostic and therapeutic context of pll

• We also find that tube sequences required for signaling interact with pelle in a yeast two-hybrid assay [5].
• We have studied the tube/pelle interaction with the techniques of surface plasmon resonance, analytical ultracentrifugation and isothermal titration calorimetry [13].

References